Treatment of fibrous cellulosic materials to impart flame resistance thereto, compositions therefor, and products thereof



Patented Aug. 22, 1950 Anne MacMillan Louko Roy H. Kienle, Bound msky, North Plainfield, Brook, and Theodore F.

Cooke, Martinsville, N. 1., assignors to American Cyanamid Company, corporation of Maine New York, N. Y., a

No Drawing. Application December 9, 1948,

Serial No. 64,4

17 Claims. (Cl. 117-137) This invention relates to a method of imparting flame resistance to a cellulosic material, more particularly a cellulosic material of the class consisting of natural and regenerated celiuloses and mixtures thereof, and specifically to a textile comprising fibers of such cellulosic materials, as well as compositions used in such treatments and to the flame-resistant cellulosic products thereof.

Various compounds and compositions have been used or suggested for use as agents for treating fibrous cellulosic and other normally flammable organic materials in order to render them resistant to flame. For a description of such compounds and compositions see the book entitled Flameprooflng Textile Fabrics," edited by Robert W. Little and published in 1947 by Reinhold Publishing Corporation, New York, N. Y., and the references cited therein. Reference also is made to the copending application of one Of us (formerly Anne MacMillan, now Loukomsky), Serial No. 691,866, filed August 20, 1946, now abandoned, wherein is disclosed and claimed a method of imparting flame resistance to cellulosic textiles which comprises impregnat ing such textiles with a phosphate of an acyclic amidlne, specifically monoguanidine phosphate, and a member of the group consisting of urea, bluret, ammonium cyanate. cyanamide and dicyandiamlde in amounts sufficient to impart flame resistance thereto upon subsequent heating, and then heating the impregnated textiles at a. temperature of at least 135 C. to form a washrast. flame-resistant finish therein and thereon.

Agents or treatments for imparting flame resistance to normally flammable organic materials properly may be classified as 1) temporary, (2) semi-durable and (3) permanent or durable, based on their durability in providing continued resistance of the treated textile or other material to flame during use. See page 6 of the aforementioned book by Little for a more complete description of these classes. The present invention is concerned primarily with certain new and useful improvements in the permanent or durable agents or treatments of the kind aforementioned.

The durable treatments heretofore used or sug gested have been of three general kinds or types:

See Little's book, supra, plete description and types.

Pages 179-284. for a comdiscussion each of these One of the main objections to the urea- Anne MacMillan 2 phosphate type of treatment is the tendering effect of the treatment on the cellulosic material whereby its tensile strength is reduced considerably. The double-bath precipitation and the metallic oxide-chlorinated body types of treatments generally yield cellulosic textiles having a harsh or still hand, so that the treated textile has a limited field of utility.

The present invention is based on our discovcry that fibrous cellulosic materials including those composed solely Or comprised mainly (that is, preponderan'tly by weight) of fibers of natural cellulose (that is, cellulosic materials of natural origin), regenerated cellulose (more particularly viscose rayons) and mixtures thereof can be rendered substantially permanently resistant to flame by suitably treating them with compositions of the kind hereinafter described. Our treated fibrous cellulosic textiles in thread, yarn, fabric or other form are unique in that they are characterized not only by their substantially permanent flame resistance but also by their improved hand or feeling to the touch as compared with the hand of textiles that have been given a double-bath precipitation or a metallic oxidechlorinated body type of treatment, thereby increasing the field of utility of flame-resistant textiles. Furthermore, these properties are obtained without excessive tendering or the textile. the treated textile in general having a tensile strength (average of the sum of the tensile strength of the warp and filling) of at least of that of the untreated textile when similarly tested for tensile strength, and in many cases a tensile strength which is even higher than that of the untreated textile.

More particularly we have discovered that flame-resistant, fibrous, cellulosic textile materials comprising or composed of fibers of natural cellulose, regenerated cellulose or a mixture thereof and which have a good hand, that is, a hand or feeling to the touch which meets the requirements of the trade, and good tensile strength characteristics are produced by impregnating the normally flammable cellulosic textile with certain materials in particular proportions or ranges of proportions which are critical in carrying the invention into efiect. A substantial proportion of the impregnant initially applied is fixedly held by the cellulosic textile after subsequent heat treatment and washing; hence the flame-resistant textiles of our invention properly may be designated as being of the "durable" type or kind.

When the flame-resistant cellulosic textiles o! the mono-, diand trialkylamine from 2 to 6 parts our invention are tested for time resistance using a vertical flame test, such as is described hereinafter, the "char length" (charred length) ordinarily is not more than about 6 inches, e. g. from 3 to 5% inches, when the textile material (e. g., cotton cloth or viscose rayon fabric) which has been treated and then subjected to 5 washes in neutral soap solution is one weighing 4 ounces about 8 inches e. g., the fabric which stantialiy less than 4 ounces, e. g., per square yard.

In practicing our invention a cellulosic material, more particularly a fibrous cellulose material of the kind defined in the first paragraph of this specification, is impregnated with ingredients comprising (1) a finely divided, oxygen-containing substance of the group consisting of tin, titanium, antimony and bismuth oxides and mixtures thereof and (2) a thermally unstable, halogen-containing thermoplastic substance, more particularly a thermosplastlc substance containing at least by weight of combined halogen and capable of rupturing under heat at carbonhalogen bonds, the ingredients of (l) and (2). which together are designated hereinafter as (A), being employed in a weight ratio of 1 part of the former to from 0.6 to 20 parts, more particularly from 0.8 to 4 parts, of the latter. Examples of the thermoplastic substances of (2) that may be employed, alone or in the form of mixtures thereof, are halogen-containing vinyl resins in which not less than 20% by weight of combined halogen is present, for instance, polyvinyl halides (e. g., polyvinyl chloride, polyvinyl bromide, etc.) polyvinylidene halides (e. g., polyvinylidene chloride, polyvinylidene bromide, etc.) copolymers of a a vinylidene halide (e. g., a copolymer of vinyl chloride and vinylidene chloride), copolymers of a vinyl halide and an acrylic ester (for instance a copolymer of vinyl chloride and an alkyl acrylate (e. g., methyl. ethyl, propyl, butyl, etc., acrylates) halogenated (e. g., chlorinated) parailins containing not less than 20% by weight of combined halogen, more particularly from about 30 or 40% up to '70 or 75% by weight of combined chloride, bromine, or other halogen, etc. In addition to the ingredients of (l) and (2), other ingredients with which the cellulosic material is impregnated are (3) a water-soluble salt (or mixtures thereof) of an oxygen-containing acid of phosphorus wherein the phosphorus atom has a valence of 5, e. g., a guanidine phosphate, a diguanidine pyrophosphate, diammonium hydrogen phosphate, sodium polyphosphate, ammonium metaphosphate, pyrophosphates, etc., and (4) a water-soluble nitrogenous substance of the group consisting of urea, biuret, ammonium cyanate, ammonium dicyanimide and mixtures thereof. The ingredients of (3) and (4), which together are designated hereinafter as (B), are employed in a weight ratio of 1 part of the former calculated as phosphoric acid (HJPOO to from i to 20 parts, more particularly of the latter, while the ingreclients of (A) and (B) are employed in a weight ratio of 1 part of the former to from 0.2 to l parts, more particularly from 1 to 3 parts, of the latter.

The fibrous cellulosic material may be impregnated with the aforementioned ingredients in one or more steps or stages. Thus, it may be impregnated with a dispersion,

more particularly .2

an aqueous dispersion, containing the ingredients mentioned in the preceding paragraph within the ranges of proportions therein specified. The treated cellulosic material is dried at a suitable temperature, e. g., at 40 or 50 to or 0., and then heated at a higher temperature within the range of C. (about 135 C.) to 200 C. (about 200 0.). During this latter heat treatment a complex reaction takes place with the result that the finished cellulosic textile in thread, yarn, fabric, felted or other form is rendered substantially permanently resistant to flame, that is to say, the finished textile is resistant to flame even after numerous laundering or dry-cleaning operations. After the heat treatuble substances which are usually present therein.

Alternatively, the fibrous cellulosic material may be impregnated first with an aqueous solution containing a guanidine phosphate or other water-soluble salt of an oxygen-containing acid of phosphorus wherein the phosphorus atom has a valence of 5 (or a mixture of such salts) and one or more of the following: urea, biuret. ammonium cyanate and ammonium dicyanimide. The water-soluble salt of the acid of phosphorus and the urea or other water-soluble nitrogenous substance, which together are designated herein as (B), are employed in ratios by weight within the ranges mentioned hereinbefore. The impregnated fibrous material is dried, heated and washed as described in the preceding paragraph with reference to the one-step process. Thereafter it is treated, as by immersion in a bath containing the same, with a liquid dispersion, more particularly an aqueous liquid dispersion. containing a finely divided metallic oxide or mixture of metallic oxides of the kind aforementioned and, also, a thermally unstable, thermoplastic substance containing at least 20%, preferably at least 40%, of combined chlorine or other halogen and which is capable of rupturing under heat at carbon-halogen bonds, e. g., polymers and copolymers of vinyl chloride. It is important that the metallic oxide or oxides and the halogen-containing thermoplastic substance or substances, which together are designated herein as (A) also be employed in weight ratios within the ranges hereinbefore mentioned. After this second treatment the treated cellulosic material is dried, e. g., by allowing it to stand at room temperature or by heating it at an elevated temperature such, for instance, as at a temperature within the range of 40 or 50 C. up to 100 or 105 C.

From the foregoing description it will be noted that the ingredients of (A) and (B) may be applied to the cellulosic material in one stage (i. e., a one-bath system) or in two stages (i. e., a twobath system); or, in other words, in the form of at least one and not more than two aqueous liquid compositions containing the same. It is important that the aqueous composition containing the ingredients of (B) have a pH of from about 3 to about 10, more particularly a pH within the range of about 3 /2 or 4 to about I or 8, since at the lower pH values (below about 3) the tensile strength losses in the treated goods are excessive while at the higher pH values (above about 10) the treated textiles have much poorer fire resistance.

Regardless of the method of impregnation of the fibrous cellulosic material with the aforementioned ingredients, it is important that the ingredients of (A) and (B) be employed in a weight ratio of 1 part of the former to from 0.2 to 8 parts, e. g., from 0.5 to 6 parts, of the latter. In all cases the total amount of the ingredients of (A) and (B) with which the cellulosic material, e. g., a cotton or viscose rayon textile material, initially is impregnated is sufllcient to impart flame resistance thereto upon heating within the range of 135 C. to 200 C. and thereafter washing to remove any residual water-soluble substances. Thus. the total amount of the ingredients of (A) and (B) with which the cellulosic material is impregnated advantageously is such that the finished flame-resistant textile contains from about to about 50% by weight (which in some cases may be as high as about 75% by weight when the matter of the hand of the treated material is relatively unimportant), based on the dry weight of the untreated textile, of washfast impregnant.

A preferred method of applying to fibrous cellulosic materials the ingredients used in practicing our invention is in the form of an aqueous dispersion containing the same. The amount or solids in such a dispersion may be varied as desired or as conditions may require, but usually the solids constitute from about 40% to about 70% by weight of the dispersion. A dispersion having excellent storage stability and which is dilutable with water to any desired extent, e. g., to about 50 or 55% by weight of solids, may be prepared, for example, as disclosed and claimed in the copending application of Maurice R. Burnell and William J. Van Loo, Jr., Serial No. 64,418, filed concurrently herewith.

When a two-bath system of applying the ingredients is employed, the first bath is prepared by dissolving in water the proper proportions of (l) guanidine phosphate or other water-soluble salt of an oxygen-containing acid of phosphorus in which the phosphorus atom has a valence of 5 and (2) urea or other water-soluble nitrogenous substance of the group previously described. This bath should be within a pH range of from about 3 to about 10. The bath also may contain a small amount, advantageously not over 7% by weight of the ingredients of (l) and (2), of a polyalkylene polyamine, preferably such a polyamine which is normally a solid or which has a boiling point substantially above 200 C., e. g., triethylene tetramine, tetraethylene pentamine, hexamethylene tetramine, etc. The ingredients are dissolved in water merely by stirring and heating at a suitable temperature, e. g.. at 40 C. to 70 C. or higher. The concentration of ingredients in the aqueous bath may be varied as desired or as conditions may require, but usually they constitute from about 30% to about 50% by weight of the aqueous solution. The composition of a typical bath is as follows:

Approximate per cent by weight Monoguanidine phosphate 15.0 Urea 28. 2 Hexamethylene tetramine 2. 0 Water 54. 8

particle size to one micron or less. To the resulting dispersion is then added a dispersion of a polyvinyl halide polymerization product, more particularly a polyvinyl chloride polymerization product, e. g., polyvinyl chloride itself or a vinyl chloride copolymer comprising mainly vinyl chloride, for instance a copolymer of, by weight, to 99% of vinyl chloride (in the copolymer molecule) and 20 to 1% of vinylidlne chloride. a lower alkyl acrylate (e. g., methyl, ethyl, etc., acrylates), or a. vinyl ester of an aliphatic monocarboxylic acid (e. g., vinyl acetate, vinyl propionate, etc.) or other thermoplastic substance containing at least 20% by weight of combined halogen and capable of rupturing under heat at carbon-halogen bonds. The mixture is thoroughly agitated until a homogeneous liquid composition or dispersion is obtained. The concentration of solids in this dispersion may be varied as desired or as conditions may require. but usually they constitute from about 10% to about 30% by weight thereof.

Any suitable apparatus may be employed in applying the treating composition (used in a. one-bath process) or compositions (used in a two-bath process) to the cellulosic material. For example, the dry or substantially dry cellulosic textile to be treated may be immersed in the aqueous composition or compositions and then passed through pressure rolls, mangles or centrii'ugal extractors to secure uniform impregnation and a controlled removal of the excess material. The cellulosic textile in fabric or other form also may be impregnated by other methods, e. g., by spraying. The wet pick-up of the composition (one-bath process) or compositions (two-bath process) by the textile may range, for example, between about 50% and about 150% by weight of the textile undergoing treatment.

The pick-up of the treating agent by the celluloslc textile material, regardless of whether the said agent is applied in one or two distinct steps or stages, is adjusted so that the finished textile contains from about 10 to about 75%, usually from 10 to 50% by weight, based on the dry weight of the untreated textile, of washfast impregnant. As has been indicated hereinbefore, when the matter of hand of the finished textile is important, it generally contains not more than about 50%, e. g., from 10 or 15% to 30 or 40%, based on the dry weight of the untreated textile. of washi'ast impregnant.

After impregnating the cellulosic textile with an aqueous dispersion containing the ingredients of both (A) and (B) or with a solution containing the ingredients of (B) only, the treated material is dried to remove most or substantially all of the liquid present therein, after which it is heated at a higher temperature of the order of about C. to about 200 C. During this latter heat treatment a substantial loss of solids takes place, which may be as much as one-half to twothirds of the total weight of the ingredients of (B) with which the cellulosic material initially was impregnated. Hence, in order to obtain a finished textile containing from 10 to 50% or, in those cases where desired up to 65 or 75% by weight, based on the dry weight of the untreated textile, of washfast impregnant, the amount of solids in the textile as initially impregnated should be sufficiently high to allow for this weight loss of solids during the heat-treating and washing steps.

In order that those skilled in the art better may understand how the present invention may be carried into effect, the following examples are given by way of illustration and not b way of limitation. All parts and percentages are by weight.

EKMLEI This example illustrates the preparation and use of a single-bath or "pad liqul in carrying the present invention into effect.

Preparation of a dispersion of antimony trioxide Preparation of pad liquor A typical formula for the preparation Of the pad liquor is as follows:

Parts Monoguanidine phosphate 151 Urea 282 Hexamethylene tetramine 20 Water 320 Antimony trioxide dispersion (prepared as described above) Aqueous dispersion containing 55-56% by weight of an unplasticlzed vinyl chloride copolymer containing between 80 and 95% by weight of vinyl chloride in the copolymer The monoguanidine phosphate, urea and hexamethylene tetramine are added to the water and dissolved therein by heating at i-50 C. The aqueous dispersion of the antimony trioxide is added to the aqueous dispersion of the vinyl chloride copolymer, and are thoroughly mixed together. (The aqueous dispersion of the vinyl chloride copolymer may be, and preferably is, the product which is available from the B. F. Goodrich Chemical Company, Akron, Ohio, under the trade name of "Goon Latex 1-15.") The resulting dispersion is added to the solution of the other ingredients, and the mass is well mixed to form a substantially homogeneous liquid composition which constitutes the pad liquor.

The vinyl chloride oopoiymer used in the above aqueous dispersion and in dispersions referred to in other examples which follow, may be, for example, a copolymer of, by weight, about 80% to about 95%, e. g., about 85 to 90% of vinyl chloride and about 20% to about 5%, e. g., about 15% to of an alkyl acrylate, more particularly a lower alkyl acrylate such, for instance, as methyl, ethyl, propyl or butyl acryiate.

Treatment of fabrics A cellulcsic fabric such, for example as cotton cloth or a viscose rayon fabric is immersed in the pad liquor and immediately passed through two rubber squeeze rolls, the pressure being adiusted so that the so-called wet pick-up" of pad liquor by the fabric is approximately 120% by weight of the dry, untreated fabric. After drying the untreated fabric. e. g., by heating at 60-70 C., the dried fabric is heated at 160 C. for from 10 to minutes. Thereafter the fabric is rinsed well in water to remove residual waterr 8 soluble substances therefrom, and again is dried (for instance at about 40 C.)

EXAMPLE 2 This example illustrates the preparation and use of two baths in carryin our invention into effect.

Both! Monoguanidlne phosphate 150 Urea 282 Hexamethylene tetramine 20 Water 548 The above-named solid ingredients are dissolved in the water by stirring and heating at 40-50 C,

Both2 Parts Aqueous dispersion containing 55-58% by weight of a vinyl chloride copolymer such as described under Example 1 199 Finely divided antimony trioxide 58 Dispersing agent, more particularly the sodium salt of a condensation product of formaldehyde and a naphthalene sulfonic acid (Tamol P) 2 Water 741 The dispersing agent is dissolved in one-half of the water and the finely divided antimony trioxide is added thereto under rapid stirring with a turbo-type mixer. The resulting dispersion is passed through a colloid mill in order to reduce the particle size to 1 micron or less. The aqueous dispersion of the vinyl chloride copolymer is diluted with the remainder of the water, the antimony trioxide dispersion added thereto, and the mass is well mixed to form a substantially homogeneous liquid composition.

Treatment qf fabrics The same procedure is iollowed in treating a celluloslc fabric with the ingredients of Bath 1 as is described under Example 1. The treated. rinsed and dried fabric is their immersed in Bath 2 and immediately passed through rubber squeeze rolls, the pressure of which is adjusted so that the wet pick-up of the disgdrsion by the fabric is approximately by weight of the dry fabric resulting from the initial treatment. The wet fabric is dried at a suitable temperature, e. g., by heating at 60-'l0 C. The flame resistance of the treated fabric is of the same general order as that of fabrics which have been treated by the onebath process described under Example 1.

Examples 3 to 16, inclusive, which follow, are illustrative of further variations in the ingredients and proportions thereof that may be used in the preparation of the treating compositions of our invention and of their use in imparting flame-resisting characteristics to cotton fabrics and rayon fabrics (other than cellulose ester rayon fabrics) using both onebath and two-bath processes. The procedure, in general, was as follows in the case of Examples 3 to 11, inclusive, 15 and 16, wherein the cellnloslc material treated was 80 x 80 cotton cloth.

Preparation of ma liquor A. son cum-earn success A dispersion of the finely divided metallic 9 oxide was prepared as follows unless otherwise specified:

Parts Finely divided metallic oxide 41.0 Dispersing agent such as described under Example 2 1.3

Water 57.7

The dispersing agent was dissolved in the water, and the finely divided metallic oxide was incorporated slowly therein under high-speed stirring. After all the metallic oxide had been dispersed, the dispersion was passed through a colloid mill (clearance: 0.002 inch). The particle size of the dispersed solid was, for the most part. one micron or less. Aggregates having a particle size up to 3 microns may be present in the dispersion.

The water-soluble salt of the oxygen-containing acid of phosphorus and the water-soluble nitrogenous substance, which ingredients are more specifically identified in the various tables which follow, were dissolved in water. using heat if necessary to effect solution. The above dispersion of the finely divided metallic oxide and the dispersion of a thermally unstable, thermoplastic substance containing at least 20% of combined halogen and capable of rupturing under heat at carbon-halogen bonds, e. g., a vinyl chloride polymerization product. more particularly a vinyl chloride copoiymer of the kind described under Example 1, were then added to the solution of the other two ingredients, and the resulting mixture was thoroughly agitated to obtain a substantially homogeneous aqueous dispersion.

B. FOR TWO-BATH PROCESS The first bath comprises an aqueous solution of the water-soluble nitrogenous substance and the water-soluble salt of the oxygen-containing acid of phosporus. The second bath contains the dispersion of finely divided metallic oxide and of the halogen-containing thermoplastic substance.

Application to fabrics A. USING ONE-BATH PRocEss Weighed strips of the cotton fabric were impregnated with the pad liquor and passed between rubber squeeze rolls. The pressure on the rolls was adjusted so that a wet pick-up of not less than 110%, unless otherwise stated, was obtained; that is, the weight of the aqueous dispersion picked up, expressed as a percentage of the weight of the dry fabric, was not less than 110%. The treated fabrics were dried at 6040 C. and then heated at a higher temperature in a forced-draft oven. The heated fabrics were thoroughly rinsed for minutes in a container into which water was running. The fabric was dried at 60-80 C. and again weighed after allowing it to stand for at least one hour in free contact with the atmosphere. The per cent "add-on" was determined by subtracting the initial dry weight from the final dry weight after rinsing, and dividing the difference by the initial dry weight and multiplying the quotient by 100.

B. USING TWO-BATH PROCESS The pad liquor of the first bath was applied to the fabric in exactly the same manner as in the one-bath process. The add-on, in general, was at least by weight of the dry fabric (80 x ac cotton) unless otherwise specified. If

less than 15% add-on was obtained, the entire application procedure was repeated on the fabric, using the same bath, until the add-on was 15% or more, based on the dry weight of the fabric.

The pad liquor of the second bath was applied to the fabric ,(pretreated as described above), using a wet pick-up of IOU-% unless otherwise specifled and dryin at 60-80 C.

Washing procedure A small oscillating washing machine was used to wash the flame-resistant fabrics unless otherwise specifled. A one-pound load was used for each wash and the fabrics were washed for 15- minute intervals using 12 liters of 0.5% neutral soap solution at 6545 C. They were spun and rinsed for from 3 to 5 minutes in lukewarm water, spun and then rinsed further by hand. Flame tests were made after washing once and five times unless otherwise indicated.

Flame tests Flame tests were made using a specially constructed apparatus and a procedure which fol lowed in general that given in ASTM Tentative Specifications Designation: D626-41T, issued 1941. Samples 2 /2 inches by 10 inches were cut with the long dimension parallel to the warp and others parallel to the fill. The apparatus consisted of a hood, a shield around the test piece, a Bunsen burner and a holder for the sample. The fabric to be tested was suspended vertically in the shield, which was placed in a hood with the fan on, the fabric being suspended in the shield by means of a clamp at the top and bottom. The door of the hood was then closed. The burner had previously been regulated to a luminous flame 1 /2 inches high, and was placed under the suspended sample so that the end of the sample extended inch into the flame. The flame was held under the sample for 12 seconds and then extinguished. The duration of after-flaming or the sample was measured by means of a sto watch. Any tendency of the sample to after-glow or smoke was noted and timed if possible. The total length of char in inches was measured by the tear length produced with a tearing weight equal to approximately 10% of the tearing strength of the unburned fabric.

The pH of the bath of pad liquor (pH of Bath 1 in the case of a two-bath process) as well as the pH of rinsings from the treated fabric after having been heated at between C. and 200 C. (that is, the so-calied "cured" fabric) were determined electrometrically with glass and calomel electrodes. The rinsings were prepared by soaking the cured fabric in a small volume of distilled water and squeezing out the excess liquid. This liquid was used in testing for pH. The fabric was then rinsed again in a large volume of running water.

In some cases the tensile strength of the treated fabrics was measured with a pendulum tester, following the strip methods of Federal Specification CCC-T-lilla. Ravelled strips (one-inch wide) as well as one-inch treated cotton tape were tested.

In this example various water-soluble salts of an oxygen-containing acid of phosphorus, wherein the phosphorus atom has a valence of 5, were employed. The water-soluble nitrogenous substance was urea. the metallic oxide was antimony In the tables which 12 case of the two-bath process C. and then cured by heat- EXAMPLE 4 The other ingredients were The antimony trid also, in varying weight A small amount e, also was employed. Both one-bath and Fur- " under the heading "Bath 2" indicates Further information on the treatment and on soluble salt in the were dried at 8040 ing for 15 minutes at 180 C follow.

that the treatment was by a one-bath process.

the results obtained are given in Table I.

o a un mmmn 1 n "m mm m nfl nmfinmw nn unmm & nu a: a m m m o. w n N m a u n B m 8 w 0888 m 7 m m 2 3773 122 0 68 2 0234 04 Q a v z m w u n n n n u n n u a n T T 1 a u a n Q I KM 4 V n Hun n nu K M m MMl-afig 0 453 4.1.444434-534334438W350W 3 m m w a 5 am W v 1 07 2 a 74275 a 8351 35B 27 37 m .H u 5 +5 1% H u .T a u u Wt in m m m u u 4.0 1 m m 628 89 1 7B 05 7 a KO 7 u mean 0 L 5 3 3 :m 5 m a n 222688853 5 2662fi330033971 7-D 2 4- 01 2 LLA LLL$KE am 7 7 7 7 4MLL.D 9 9 9 9 fl & 7 6 am 2 6 5 1am Table I ride copolymer such e l, more particud about of an 5 -containing thermoplasmpl lymer of, by weight,

bath and a two-bath procvinyl chic and the halogen unplasticized copo oi vinyl chloride an The ingredients, which were aptrioxide,

tic substance was a as that described under Exa lai'ly an about 85% alkyl acrylate plied by both a oneo n in 3 mu 1.. 5 5 5 5 3 mm m wmmmmfimwm mmmmmfimummmmwmmmmw m mwnmmmmnmmnmmuuw aumm w B 00 BMI 3 3 .m m? hmmnnnnnu anddamn unuunannmuuunuuudunnnnunnunnu nuuu A n n 0 I D 2.0135235140681468161 3.05 1164 238 02 1 A. 2 MW SH ulu m 111mm. 11.1 11 mm mm mm a a m w 41 1 10 msandmanuunmnnuunuunnnnnnnnnnuuanand unnu a a mu rhihmnummomlal 12.08912.082912589128915932789211755581 soc- 9 5 2 2 W a 1 maaui nmaaa m w I u I uwnn nwuwn .0 m m m H a a m a mm m a m m w a w s a m a sea w m a m m p 0 a u n "aw" I n B uh .h .M 3. .LU mmm 1 "h m .p u n. a" 1 .w umzoli n n s H m "a a mean 000m Tm I m 5mm u a .Q. L. PPP. .09 a B .1 L w. an. .nmmmmmmwm e nmwawhmwmm mnma I a J m mwmm mmmnmmnnnmnmnnmm Dnpmmmm mm mmmmmm mpm mmmm 11D. Balsa a t .l u n n o n snnnuunnx mmmmnssi lws a s In this example the water-soluble salt 0! an oxygen-containing acid of phosphorus was mono.- guanidine phosphate the same as in Example 3. oxide and the vinyl chloride copolymer were use 70 in varying amounts and ratios of the one to the other. of a buffering agent, more particularly a polyalkylene polyamine and specifically hexamethylene tetramin taining the water- 78 two-bath application methods were used.

11 hates 1 in this and lee mad lead acid a i r i u t 47- pymz p' fi mffi't Per cent Urea plus salt 43.3 Antimony trioxide 5.8 11.0

so, to own in Table I.

The treated textiles after immersion in the treatacid, from which the about 32-50% metap ratio of urea to salt as salt and Norm-The polyphosphoric about 34% orthophosphoric acid,

1 The weight the latter calculated as HaPO as s esss as herelnbefore described, were used in the following weight percentages Vinyl chloride copolymer Water ing composition of the one-bath process or after immersion in the first bath con ther details on weight percentages of ingredients EXAMPLE 6 are shown below: P t In this example varying amounts or ammonium Ur er dicyanimide. ammonium cyanate and biuret were used either wholly in place of urea or in comg tg am 5 bination with urea in the case of biuret, the other i zi Se T bl ingredients being monoguanidine phosphate, antigfi z gt sgg ag; a 11 mom trioxide and a vinyl chloride copolymer water Remainder such as was employed in the prior examples.

1 Table IV shows the ratios of ammonium dicy- Further information on the treatment and on o animide, ammonium cyanate and o! biuret plus the results obtained are given in Table II. urea to monoguanidine phosphate as such and Table I! Flame Test Vertical Per Cost Per Cent Total Dry A Per Time After Glow, Wei in mm For om Vinyl Add-On pH pH ent if i g Soc.

B so: to 817101 Chloride Bath mum s Tensile Copoiymer in Bath Oopclymcr K Slims! in mm Bath 1 mm 2 1 Wash 5 Washes 1 Wash 5 Washes 1. 75:1 10. o a 1 1a 17 3% 4 1. 11:1 a4 5.115 is 14 a a m 1.111 a as 11 4 2 a 1:10 0.00 9.1 :12 a 4 2 a 1:20 0.411 10. 2 a4 4 4 o o 1:40 0.2.: 10.2 32 a 4 an o 3 EXAMPLE 5 calculated as HaPO4. The ingredients were applied by a two-hath process, the second bath being an aqueous dispersion containing, b weight. 5.8% of SbzOs and 11% of the aforementioned copolymer. Further information on the treatment and on the results obtained also appears in In this example the ingredients employed were the same as in Example 4. The weight ratio 0! antimony trioxide to vinyl chloride copoiymer was 1.121, these ingredients together being designated as "A." The weight ratio of urea. to monoguanidine phosphate was 2:1, while the weight Table IV.

Table IV 1 h Flame Test We t Ratio 0 s na e Substance m- H pH Vertical Charred Time After Glow, N itrogcnous Substance Emma Length, Inches Sec.

Salt as Bait as such HPo Bath 1 Bath 2 1 Wash 5 Washes 1 Wash 5 Washes Ammonium dicyauimide 12 15:1 :1 19 2) 4.8 6.5 3 5 4 14 Do 1:1.6 1:! 18 lb 4.2 3.3 3 3% 3 3 Ammonium cyanate.-. 12.511 37:1 16 3) 9.1 7.5 3 3 3 17 DO 1:1.6 1:1 21 18 6.1 6.3 3% 3 9 ll Biuret and urea 1:1. 6 1:1 211 17 s. 1 a1 4% 492 0 2c 1 Urea wazlprcsent to such an extent as to make the sum of the urea and bluret equal to about by wieght of an aqueous solution thereof. 4110 solution thout the urea) having first been saturated at 00 C. with biuret.

ratio of urea to hexamethylene tetramine was EXAM-E '7 5 e ea. o fl d e Phosphate and In this example a diil'erent halogen-containing hexamethylene tetramine together are designated th rmoplastic substance, more particularly a as B." The weight ratios 01' A to B were varied U chlorinated paraflln containing about by 8 Shown in Table which 8180 gives further weight of combined chlorine, was used in place 01' information on the treatment and on the results a vinyl chl ride copolymer. Further details on obtained. weight percentages of ingredients ar given below:

Table I Per cent Urea 28.2 cent Dry Flame Tm Vertical Monoguanidine phosphate 15.1 gag ng row A -on mm, "ifig Antimony trioxide 15.0

LB Strenrgh hl;o$1 Chlorinated paramn containing about 60% Bath] Bath2 or B vast, awash wbze weight of combined chlorine a r 5:1 4 to +12 4 4 The ingredients were applied by a two-bath g 4 if; 3 process as hereinbefore described. Further information on the treatment and on the results obtained are given in Table v.

"Values latex which was employed in each of the previous examples. The ingredients were applied by a one-bath process. For additional details of the see Table VII. The percentage proportions shown in this table refer to the per cent each ingredient in the aqueous bath, water constituting the remainder or the bath.

See.

In this example washing of the treated fabrics was done in pint Jars, each of which contained a 6-inch square sample of fabric, 20 steel balls and 200 m1. 0! a 0.5% neutral soap solution heated to 180 F. The jars were revolved for minutes.

See Table VIII for additional details of the Time Alta Glow,

1 Wash Table VII Flame Test lWashos a dispersion which (118- treatment employed and the results obtained, persion was stabilized with ammonium hydroxide Vertical Charred Length, Inches Table V Bath 2 Add-On Bath 1 we ht Ratlo olo lorlnatod Psniln to SbiOl This example iiistrates the use of containing the essential ingredients as more fully described in the aforementioned copendlng application of Maurice R. Burnell and William J. Van Loo. Jr., Serial No. 64,418. It

EXAMPLE 9 This example illustrates the use of other oxide and stannic oxide, instead of antimony trioxide in the treating compositions. The vinyl chloride copolymer (used in the form of an aqueous dispersion) was the same Geon copolymer treatment and the results obtained.

I r gre 2101 P. P w m mn u a 5 2 a m M H "A. m uaawvahh 21 n kt m. w m m m. m r e em m w 5 M tp n e 1 id a: e P n n "a a 3 u m m mwn w H Tm n mm s. B m a m m mma m mm .W u m W w M Ma .m m R m m. a m m wmmm m n mama w m m mam. n n; wa h h 66 H r m h s a s F M. cl 5 t mm W 1 3 n? a a v 1 were m a? a 3...... an a i m-1m t 6W 2 000 fig? Mm ms we ma a a We B 88 p- B n mmmmmw. hawk m 2.... D. W V. MM llli 55!: a an .1 m mmm m m =3: e wmm Ga c r E I .7 H mm; 53% 7 m e emw m m wm iege u m w mi m m W W 2. s 0 a E4 tut 8 e n 22 e E fl mu m .u m 552m me H m rlna .ehe o m T 870 .6 m m mm m fiamfia n. O 253; 5.96m ww mmmflwwmmmmamm dousfifiauwohm m awn f m enn aam e o .1 1x 11 Qu et m% m mdmmmm iu mfi m fi sh 3 m .m. H mfitm m m m m n afi kshia afifi ssm hw-wlal 34?... .0 Menu-ham J1 m m r a d e k QB o eeseoasr 55. m p. v o t 5 s ma mm ma w n as i. can 232:8 h m em x m c m. um e W .boaeQsEneEoE .afissefiez m m hwm v. 52 5 m wwm a as m mm m ewemm mm w b e s im sfl o ode o ea-poem nm m m m w naazocnsomom define: e e evv. 0 u I v 0 m n W 0 w W n t bf B m P 2 9; E5350 3 2% 225 00 m md wwa m 0233 :88 522. 5 W 525 M .0 uflflowac om mm... m n o mr Me I 555 c P wew a mumm iw W s m mam 285: mm m m mmumw wmmd M mama nm w n "L m e I d o m 008$.- 2a 11 mmmwmm mmwmmm m 3 32 I ame-gamma 5 1 M6 c8 r a: .23 383m 1 m flwmmhmmflamnamo m wmm metallic oxides, more particularly bismuth tri- Table VIII Conditions Per Cent Per Cent Total Flame Test Vertical Charred Curing ,YE'g 33f; Vinyl gag? Add-0n Length, Inches to 'r tanium gggggg 111011113 "0. Minutes in Bath in Bath 1 1 Bath 2 1 Wash 11 Washes Washes 140 40 121 2. 5 2. 5 20 3 5 4% 5 140 40 1:1 5. 0 5. 0 1D 8 5% 6 5 100 15 1 =1 e. u a o 17 11 e t t 140 40 1:1 7. 5 1. a is 14 e a a 1 1m 15 1:1 1.5 1.5 19 is s a 1 o 14a 40 1:1 2.6 as 24 o 4 a 01/ 140 40 1:1 11. o a. 0 2a 0 4 m 5 mo 15 11:1 5.0 2.5 as o s a 6 EXAMPLE 11 strength or the untreated and treated cotton In this example ammonium dicyanimide or ammonium cyanate was used as the water-soluble nitrogeneous substance and monosodium or disheeting and rayon suiting, and the results of flame tests on both kinds of treated goods after being rinsed and after the aforementioned sodium phosphate as the water-soluble oxygenwashes. The rinsed and washed samples were containing acid of phosphorus. The metallic pressed dry before testing.

Table X Horizontal Flame Tests Weight Retention Tests Vertical Flame Tests Ht. 0! (we Retained. Per cent) il-m rii Hume Burned Area m as.) 1$}, ath i n Per Cent mused 1Hr. 3 Hr. 5Hr. 1 Hr. 3 Br. 5 Hr. mused 1 Hr 3 Hr 6 Hr Pounds) Applied Wash Wash Wash Rinsed Wash Wash Wash Wash Wash Wash 100 x 60 Cotton Sheeting. Un-

treated..- U O 137 100 x 60 Cotton Sheeting,

Treated:

6 cure 38 E 18 13 2 4 2.5 24 2.5 3.3 3,3 132 cnre 39 21 21 l8 l6 2 4 2. 4 2. 4 2 4 3. 2 3. 3 1% euro 40 28 21 16 14 24 2.4 2.4 2.4 3.3 3.1 130 Rayon Suiting, Untreated C 0 87 Rayon Suiting, Treated:

ii'cure 18 1.9 18 1.8 2.5 2.8 m lll'oure 18 1.9 1.8 1.8 26 2.6 m 16' cure 1 8 1.9 1.8 1.8 2. 5 2.5 2 11 CComplete charring of sample.

oxide was antimony trioxide and the halogencontaining thermoplastic substance was a vinyl chloride oopolymer such as was employed in prior examples. The ingredients were applied by a two-bath process, the second bath being an aqueous dispersion containing, by weight, 5.8% of $1120: and 11% of the aforementioned eopolymer. Further information on the treatment and the results obtained appears in Table Di.

It will be noted from Table X that the results or flame-resistance tests were excellent at all oi the cure times employed and that the loss in tensile strength, 11' any, or each of the treated fabrics was very little; and that in one case (treated rayon suiting using a 5-minute cure) there was an actual gain in tensile strength.

The treated fabrics were analyzed for phosphorus. The results are shown in Table XI.

Table IX L Flame Tests Per Cent Dry Weight Ratio T an Add 0 iNitro 93 H Vertical Charred Time Aiter Glow Nitrogenous Substance Salt 0 First inastgggeus gukt Bath mg! Length, Inches Sec.

Bath 1 Bath 2 1 Wash 5 Washes 1 Wash 5 Washes Amonium dicyanimide.-- Disodium phosphaie 1:1. 4t l0 l0 0. 8 4. 9 4 4 0 1 Do Molnotzodium phos- 1:1.2 19 19 5.1 4. 7 4% e 0 I a Ammonium emanate.-- D odium phosphate 1:1. ill 10 9.1 8.5 4% 4 10 Do Monosodium phosphnta 112 15 18 6.2 0. 4 3 4% 5 10 EXAMPLE 12 The results of phosphorus determinations are re- The treating composition used in this example was essentially the same as that described under Example 1. The aqueous dispersion contained approximately 57% by weight of solids. Heavy es rayon suiting and 100 x 60 cotton sheeting were padded through the dispersion, dried at about 104.5 C. and then cured by heating for 5, 10 or 15 minutes at 160 C. Table X gives the weightretention values of the cured samples of cotton sheeting as initially produced, after being rinsed in warm water and after washing for 1, 3 and 5 hours in a 0.1% soap solution at 160 F. in the case of the cotton sheeting and at F. in the oaseoi'therayonsuitlng.asweliasthetensile 7s 19 will be seen that the phosphorus content of the treated fabric remains substantially constant on prolonged washing of the fabric in a soap solution.

This example illustrates the results obtained with various concentrations (57%, 42.6% and 28.5% solids) oi the same treating ingredients in the same proportions used in the treating comosition of the prior example in imparting flame resistance to diflerent fabrics, more particularly to 100 x 60 untreated cotton cloth. cotton marquisette, rayon challis and rayon netting. The wet pick-up was approximately 80% by weight From Table arr it It will be noted in Table XII that the treatment of the rayon netting resulted, in all cases, in a substantial increase in the tensile strength of the treated fabric as compared with the untreated netting, the percentage increase being more than 21%. This was quite surprising and unexpected. and in no way could have been predicted.

EXAMPLE 14 The treating composition used in this example was essentially the same as that employed in Examples 1 and 12. The aqueous dispersion was applied to various cotton fabrics by a one-bath process. Dryingand curing of the treated fabrics of the dry fabric. in the case of the cotton goods, were carried out under essentially the same conabout 100% by weight of the dry-fabric, in the case ditions described in the prior example. The of the rayon ehallis and about 150%, by weight of treated fabrics were given washes of 1 hour each the dry fabric, in the case of the rayon netting. in a 0.1% soap solution at 160 F. The results are The time of curing was 5 minutes at 160 C. shown in Table XIII.

Table I!" I'lsnls 'lsts Bolero wulllng liner Washing m Material more W Avg. After- A Char Avg. After- Av Char Glow in See. in Glow in See. in Enables Warp Fill Warp Fill Warp Fill Warp Fill Warp Fill Untreated Duck. l8! l3! Treated Dunk 2 a 2.15 2s 1s 1a are as ms 120 Untreated 21 11 Treated ll ul'sel o o s. 1 4 1 o o s. 1 a as is s ntrented Iv lte 47 3O Treated white iloc o 1 s. 1 an o 2 as 4 as 40 a Untreated unbleached muslin 4': 4s Treatedunbleaclledmuslln-.-. o o as as i 1 us 4.0 44 so Untreated flowered hen-1n; 10s or Treated flowered herringbone- 1-2 2 a. 25 8. 0 4 4 i. 6 4. lb Q as Unh-eated maroon herring 118 47 maroon herrin bone..." 1-: 1 :11 a1 a 1.0 4.0 as 111 42 Untreated white twill can. ml or Treated white twill }ean.--- 1 o as a s 2 1 4.15 s. c we so The other conditions of treating and testing were 15 the same as in Example 12. The results of flame tests and tensile strength tests are given in This example illustrates the results obtained Table x11. using polymeric vinyl chloride (polyvinyl chlo- Table XII Horizontal Flame Tests (M. an. Vcrfltlfl] Flame Tests (Ht. of Total of burned area/in.) burned area in inches) 5:-

1 H a n a n 1 n:- Hr s n staph I. I. I. 7. Wash Wash Wash was Wash Wash Pounds) 100 x on Cotton Cloth, Untreated--.- 0 0 m 100 r so Cotton Cloth, treated 51% solids in poll 11 a2 2.3 2.3 as 3.4 as a1 1.4 141 100 s -otton Cloth, treated 28.6% solids in pad ll lor a 1 3.2 2. a z 1 4. s 4.0 4.1 4.2 140 x 60 otton Cloth, treated 42.0% solids in pad liquor -1. 2. 4 2.4 2.4 a 4 a4 a 2 as 1.1 142 Cotton marquisette. Untreated.... 0 C 54 Cotton marquisette, treated 57% solids in pad 11 2.1 2.2 2.2 2.3 as as 3.5 so 40 Got marqulsette, treated 43.6% solids in pad Lisbon. 2. 2 2.2 as 2.4 as as as 4.21 41 Rayon hallis, Untreated C O 138 Rayon Challis, treated 57% solids in pad liquor. 2.1 21 2.1 11 as as a4 a: no Rayon Challis, treated 42.0% solids In pad liquor 22 as 2.11 a: as as as as 141 Rayon Challis, treated 28.5% solids in pad liquor.-... a s 21 as 17 4.1 a1 so 4.: m Rayon nctt Untreated.... 0 O 42 Rayon netting, treated 57% solids in pad liquor 1.0 2.0 2.0 as a4 a4 as 52 Rayon netting, treated 42.6% solids In pad llr lum- Lil 2-0 2-0 I. 8.8 3-2 3.7 51 Rayon netting, treated 3.5% solids ln pad liquor 2-1 2-0 3.0 8.8 3.3 a. 3.8 61

(l-Complete charting of sample.

processes in essentially the viously has been described.

One-bath process COMPOSITION on BATH Parts (approx) Monosuanidine phosphate 151.0 Urea 282.0 Hexamethylene tetramine 20.0

Antimony trioxide introduced in the form of an aqueous dispersion prepared as de- Essentially the same procedure was followed in applying the composition to 80 x 80 cotton cloth as that described under Example 1.

Twmbath process COMPOSITION OF BATH 1 Essentially the same ample 2. Further information on the treatment and on the results obtained appears in Table XIV.

Table XIV Per Cent Total Flame Tests, Verti- Dry Add-On cal Charred Length, Inches 1 Wash Washes A verage Per Cent Loss In Tensile Strength Bath 1 Bath 2 Compositions were prepared in essentially the same manner as described under Example 1, using the following proportions oi ingredients:

Parts Monoguanidine phosphate 75.5 Urea 141.0 Basic material 10.0 Water 160.0

Aqueous dispersion containing about 55.5% by weight of a vinyl chloride copolymer such as described under Example 1---- Aqueous dispersion containing about 41% by weight of $1320: and about 1.3% by weight of a dispersing agent, more particularly a sodium salt of a condensation product of formaldehyde and a naphthalene sulionic acid (Tamol P) 68.0

The following basic substances were employed in individual compositions:

. Triethylene tetramine.

. Tetraethylene pentamine.

. Hexamethylene tetramlne.

. Calcium carbonate in the form of a 40% aqueous dispersion using 0.5% of the aforementioned dispersing agent and water from the 160 parts mentioned in the formula.

Essentially the same procedure was employed results obtained appears in Table XV.

Table X V Basic substance 1 2 3 4 Per cent wet ick-up 127 121 Per cent tota dry add-on 29 30 33 31 pH of bath 0.3 6. 3 5. 7 5 pH of rinsings 6. 7 6. 5 6. 1 6. 0 Average per cent loss or gain in tensile str 2 0 +3 3 Vertical flame tests:

barred length in inches I wash 4.3 4.2 4.0 4.3 5 washes 4. 8 4. 1 4. 4 4. 4 Alter glow in seconds 1 wash 7 8 7 6 5 washes l0 15 20 10 phosphoric acid.

Any 01' the oxides of tin, titanium, antimony about to about 99% of vinyl amples of which materials have been given hereinbeiore. Additional examples include the halogenated diphenyls (e. g., p ntachlorodiphenyl, pentabromodiphenyl, etc.) and the halogenated (e. g., chlorinated, brominated, etc.) naphthalenes, which compounds contain at least by weight of combined chlorine, bromine or other halogen. We prefer to use polyvinyl chloride or a vinyl chloride copolymer containing at least 00% by weight of combined (1. e., combined in the copolymer molecule) vinyl chloride, more particularly a copolymer of, by weight, from chloride and from about 20% to about 1% of an acrylic ester, specifically an alkyl acrylate such, for instance, as methyl, ethyl, propyl or butyl acryiate.

It is important that the water-soluble nitrogenous substance, the water-soluble salt of an oxygen-containing acid oi. phosphorus, the metallic oxide and the halogen-containing thermoplastic substance be used in proportions within the ranges given in the eighth paragraph oi this specification. As shown by the numerous examples, especially in the tables, the proportions may be considerably varied within these broader ranges and still obtain a finished textile which is resistant to time even after numerous laundering or dry-cleaning operations and without excessive tendering (in many cases without any tendering) oi the textile. Furthermore, by using the ingredients within the proportions stated hereinbeiore, a flame-resistant textile having a good band or feeling to the touch is obtained. As will be readily appreciated by those skilled in the textile art, the matter of hand or feeling to the touch is, for most applications, oi considerable importance irom both saleability and utility standpoints.

The fundamental treating compositions of this invention may be modified by incorporating therein various modifying agents which aid in further improving the flame-resistant characteristics of the treated cellulcsic material or which facilitate the technique of application. For instance, the compositions may also contain minor amounts (e. g., from 1 to by weight of the total solids content) of such glow retardants as the glow-retarding borates, phosphates, pyrophosphates, etc., e. g., zinc borate, zinc phosphate, sinc ammonium phosphate, stannic phosphate, phenyl diamido phosphate, melamine pyrophosphate, etc. Agents which have a buifering eifect on the composition after being applied to the fabric or other textile, e. g., calcium carbonate, magnesium oxide, hexamethylene tetramine and other polyalkylene polyamines, etc., may be incorporated into the treating compositions as desired or as conditions may require.

The pH of the bath containing the ingredients of (B) in a two-bath process or the bath containing all of the ingredients in a one-bath procees should be adjusted to a pH (glass electrode pH) within the rail of item about 8 to about 10, e. g., a pH of from about 8% or 4 to about I or B, ii the pH of the aqueous composition contalning these ingredients (water-soluble salt of the oxygen-containing acid of phosphorus and water-soluble nitrogenous substance) is not initially within a pH range of from about 3 to about 10. Preferably the pH of the aqueous composition containing the ingredients of (B) is between 4 and 'l, e. g., about 6.

The present invention is applicable to the production of a wide variety of flame-resistant cellulosic materials, e. g., wearing apparel or all kinds, especially children's clothes and clothing used by the armed forces, curtains, draperies, sheeting, furniture coverings, linings for electric blankets, net fabrics, non-woven fabrics, cbenilles, etc., and which are made of cellulosic materials such as are described in the first paragraph of this specification and elsewhere herein. Other applications of the flame-resistant products of our invention include those described in Chapters VII and VIII of the aforementioned book, edited by Little, entitled Flameproofing Textile Fabrics.

The terms "flame resistance" and flame-resistant" as used herein and in the appended claims with reference to cellulcsic materials, specifically cellulcsic textiles, are used generically to include within their meanings treated cellulosic materials (e. g., treated fabrics) which, after ignition, will continue to burn at a relatively slow rate as well as those which, after ignition, will burn over only a limited area beyond that directly exposed to the source of ignition and which may be specifically designated as fireresistant" cellulosic materials. It will be apparent from the examples herein given that most of the products of our invention properly fall within the specific classification of fire-resistant cellulosic materials.

The terms "textile and textile material" as used generically herein and in the appended claims include within their meaning filaments. fibers, rovings, slivers, threads, yarns, twisted yarns, etc, as such or in woven, ielted or otherwise iormed fabrics, sheets, cloths and the like.

We claim:

1. A method of imparting flame-resistance to a cellulcsic textile material of the class consistin; or natural celluloses, regenerated celluloses and mixtures thereof, said method comprising impregnating said material with an association of (1) an aqueous liquid composition having a pH of from about 3 to about 10 and containing (0) ingredients initially in the iorm of a water-soluhle salt of an oxygen-containing acid of phosphorus wherein the phosphorus atom has a valence of 5 and a water-soluble nitrogenous substance selected irom the group consisting of urea, biuret, ammonium cyanate, ammonium dicyanimide and mixtures thereof, said salt of an oxygen-containing acid of phosphorus and said nitrogenous substance being employed in a weight ratio of 1 part or the former calculated as HrPOe to from i to 20 parts of the latter, and (2) an aqueous liquid composition containing (0) ingredients comprising a finely divided, oxygen-containing substance of titanium, antimony and bismuth oxides and mixtures thereof, and a thermoplastic halogen-containing, organic substance having at least 20% by weight of combined halogen and capable of rupturing under heat at carbon-halogen bonds, said finely divided oxygen-containing substance and the group consisting of tin,

said thermoplastic substance being employed in a weight ratio of 1 part oi the former to from 0.6 to 20 parts of the latter, and the said ingredients of (a) and (b) being employed in a weight ratio of 1 part of the latter to from 0.2 to 8 parts oi the former: heating the textile material after it has been impregnated with a composition comprising the aqueous liquid composition of (1) at a temperature within the range of about 135" C. to about 200 C.; and washing the resulting material to remove any residual water-soluble substances therefrom, the total amount of the compositions of (1) and (2) with which the cellulosic material initially is impregnated being such that the finished flame-resistant textile contains from about to about 75% by weight, based on the dry weight of the untreated textile, of washfast impregnant.

2. The process of claim 1 wherein the aqueous composition of (l) and the aqueous composition of (2) are applied simultaneously in a single bath.

3. A method as in claim 1 wherein the cellulosic textile material is a cotton textile material.

4. A method as in claim 1 wherein the cellulosic textile material is a viscose rayon textile material.

5. A flame-resistant cellulosic material of the class consisting of natural celluloses, regenerated celluloses and mixtures thereof, resulting from the method of claim 1.

6. An aqueous dispersion, suitable for use in imparting flame-resistance to cellulosic textile materials selected from the group consisting of natural celluloses, regenerated celluloses and mixtures thereof, having a pH of from about 3 to about 10 and comprising (i) a finely divided, oxygen-containing substance of the group consisting of tin, titanium, antimony and bismuth oxides and mixtures thereof and (2) a thermoplastic halogen-ccntaining organic substance containing at least 20% by weight of combined halogen and capable of rupturing under heat at carbon-halogen bonds, the ingredients 01' (l) and (2), which together are designated hereinafter as (A), being employed in a weight ratio of 1 part of the former to from 0.6 to 20 parts of the latter and being dispersed in water containing ingredients initially in the form of (3) a water-soluble salt of an oxygen-containing acid of phosphorus wherein the phosphorus atom has a valence of 5 and (4) a water-soluble nitrogenous substance of the group consisting of urea, biuret, ammonium cyanate, ammonium dicyanimide, and mixtures thereof, the ingredients of 3) and (4) which together are designated hereinafter as (B), being employed in a weight ratio of 1 part of the former calculated as HsPOq to from 1 to 20 parts of the latter, and the ingredients of (A) and (B) being employed in a weight ratio of 1 part of the former to from 0.2 to 8 parts of the latter.

7. The aqueous dispersion of claim 6 wherein the finely divided oxygen-containing substance is antimony trioxide, the thermoplastic halogencontaining organic substance is a vinyl chloride polymerization product, the water-soluble salt of an oxygen-containing acid of phosphorus is monoguanidine phosphate and the water-soluble nitrogenous substance is urea.

8. A method of imparting flame-resistance to a textile material comprising fibers of a cellulosic material of a class consisting of natural celluloses, regenerated celluloses and mixtures thereof, said method comprising impregnating said textile material with the composition of claim 6, drying the impregnated material, heating the dried material at a temperature within the range of 135 C. to 200 C. and washing the resulting material to remove any residual water-soluble substances therefrom, the total amount 01 said ingredients or (A) and (B) with which the cellulosic textile material initially is impregnated being such that the finished flame-resistant textile contains from about 10% to about 50% by weight, based on the dry weight 01 the untreated textile, of washfast impregnant.

9. A method 01' imparting flame-resistance to a textile comprising fibers oi a cellulosic material oi the class consisting of natural celluloses, regenerated celluloses and mixtures thereof, said method comprising impregnating said textile with an aqueous dispersion having a pH within the range of 3 to 10 and comprising (1) a finely divided oxide of antimony and (2) a thermoplastic vinyl chloride polymerization product containing at least 40% by weight of combined chlorine, the ingredients 01 (1) and (2), which together are designated hereinafter as (A), being employed in a weight ratio oi 1 part of the former to from 0.6 to 20 parts of the latter and being dispersed in water containing ingredients initially in the form of (3) a water-soluble guanidine phosphate and (4) urea, the ingredients oi (3) and (4), which together are designated hereinafter as (B), being employed in a weight ratio 0! 1 part of the former calculated as H3PO4 to from 2 to 20 parts of the latter, and the ingredients of (A) and (B) being employed in a weight ratio of 1 part of the former to from 0.2 to 8 parts of the latter, drying the impregnated material, heating the dried material at a temperature within the range of 135 C. to 200 C., and washing the resulting material to remove any residual water-soluble substances therefrom, the total amount of the ingredients of (A) and (B) with which the cellulosic textile material initially is impregnated being such that the finished flame-resistant textile contains from about 10% to about by weight, based on the dry weight of the untreated textile, of washfast impregnant.

10. A flame-resistant textile material of the c1as? c0nsisting of natural celluloses, regenerated celluloses and mixtures thereof, resulting from the method of claim 9.

11. A method as in claim 9 wherein the watersoluble guanidine phosphate of (3) is monoguanidine phosphate.

12. A method as in claim 9 whereinthe aqueous dispersion also contains a small amount, not exceeding about 7% by weight of the ingredients 01' (B), of a polyalkylene polyamine having a boiling point substantially above 200 C.

13. A method of imparting flame-resistance to a textile comprising fibers of a cellulosic material oi the class consisting oi natural celluloses, regenerated celluloses and mixtures thereof, said method comprising impregnating said textile with an aqueous solution having a pH within the range of from 3 to 10 and containing ingredients initially in the form of (l) a water-soluble salt of an oxygen-containing acid of phosphorus wherein the phosphorus atom has a valence of 5 and 2) a water-soluble nitrogenous substance of the group consisting of urea, biuret, ammonium cyanate, ammonium dicyanimide and mixtures thereof, the ingredients of (l) and (2), which together are designated hereinafter (B), being employed in a weight ratio 01 1 part 01 the former calculated as 311904 to from 1 to 20. parts of the latter; heating the impregnated textile at a temperature within the range of 135 (2. to 200 0.; washing the resulting textile to remove any residual water-soluble substances therefrom; impregnating the heated and washed textile with ingredients comprising (3) a finely divided, oxygen-containing substance of the group consisting oi tin, titanium. antimony and bismuth oxides and mixtures thereof and (4) a thermoplastic halogen-containing organic substance containing at least 20% by weight of combined halogen and capable oi rupturing under heat at carbon-halogen bonds, the ingredients 01' (8) and (4), which together are designated hereinafter as (A), being employed in a weight ratio 1 part 01 the former to from 0.6 to 20 parts of the latter, the ingredients of (A) and (B) being employed in a weight ratio of 1 part of the iormer to from 0.2 to 8 parts of the latter, and the total amount of the ingradients of (A) and (B) with which the said textile is impregnated being such that the flnished flame-resistant textile contains from about 10% to about 75% by weight, based on the dry weight of the untreated textile, o! washi'ast impregnant.

14. A flame-resistant cellulosic material of the class consisting 01 natural celluloses, regenerated celluloses and mixtures thereof, resulting from the method of claim 13.

16. The method 01' claim 13 wherein the watersoluble salt or an oxygen-containing acid of phosphorus is a guanidine phosphate, the watersoiuble nitrogenous substance is urea, the finely divided oxygen-containing substance is antimony trioxide and the thermoplastic halogen-containing substance is a vinyl resin containing at least by weight or combined chlorine.

16. A method as in claim 15 wherein the textile is a cotton fabric material.

17. A method as in claim 15 wherein the watersoluble guanidine phosphate is monoguanldine phosphate.

- ANNE MAcMILLAN LOUKOMSKY.

ROY H. KIENLE. THEODORE F. COOKE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,099,697 Groebe Aug. 10, 1937 2,178,825 Clayton et al Nov. '7, 1939 2,357,725 Bennett Sept. 5, 1944 2,413,163 Bacon Dec. 24, 1946 2,427,997 White Sept. 23; 1947 2,461,538 Fischer Feb. 15, 1949 

1. A METHOD OF IMPARTING FLAME-RESISTANCE TO A CELLULOSIC TEXTILE MATERIAL OF THE CLASS CONSISTING OF NATURAL CELLULOSES REGENERATED CELLULOSES AND MIXTURES THEREOF, SAID METHOD COMPRISING IMPREGNATING SAID MATERIAL WITH AN ASSOCIATON OF (1) AN AQUEOUS LIQUID COMPOSITION HAVING A PH OF FROM ABOUT 3 TO ABOUT 10 AND CONTAINING (A) INGREDIENTS INITIALLY IN THE FORM OF A WATER-SOLUBLE SALT OF AN OXYGEN-CONTAINING ACID OF PHOSPHORUS WHEREIN THE PHOSPHORUS ATOM HAS A VALENCE OF 5 AND A WATER-SOLUBLE NITROGENOUS SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF UREA, BLURET, AMMONIUM CYANATE, AMMONIUM DICYANIMIDE AND MIXTURES THEREOF, SAID SALT OF AN OXYGEN-CONTAINING ACID OF PHOSPHORUS AND SAID NITROGENOUS SUSTANCE BEING EMPLOYED IN A WEIGHT RATIO OF 1 PART OF THE FORMER CALCULATED AS H3PO4 TO FROM 1 TO 20 PARTS OF THE LATTER, AND (2) AN AQUEOUS LIQUID COMPOSITION CONTAINING (B) INGREDIENTS COMPRSING A FINELY DIVIDED, OXYGEN-CONTAINING SUBSTANCE OF THE GROUP CONSISTING OF TIN, TITANIUM, ANTIMONY AND BISMUTH OXIDES AND MIXTURES THEREOF, AND A THERMOPLASTIC HALOGEN-CONTAINING, ORGANIC SUBSTANCE HAVING AT LEAST 20% BY WEIGHT OF COMBINED HALOGEN AND CAPABLE OF RUPTURING UNDER HEAT AT CARBON-HALOGEN BONDS, SAID FINELY DIVIDED OXYGEN-CONTAINING SUBSTANCE AND SAID THERMOPLASTIC SUBSTANCE BEING EMPLOYED IN A WEIGHT RATIO OF 1 PART OF THE FORMER TO FROM 0.6 TO 20 PARTS OF THE LATTER, AND THE SAID INGREDIENTS OF (A) AND (B) BEING EMPLOYED IN A WEIGHT RATIO OF 1 PART OF THE LATTER TO FROM 0.2 TO 8 PARTS OF THE FORMER; HEATING THE TEXTILE MATERIAL AFTER IT HAS BEEN IMPREGNATED WITH A COMPOSITION COMPRISING THE AQUEOUS LIQUID COMPOSITION OF (1) AT A TEMPERATURE WITHIN THE RANGE OF ABOUT 135*C. TO ABOUT 200*C.; AND WASHING THE RESULTING MATERIAL TO REMOVE ANY RESIDUAL WATER-SOLUBLE SUBSTANCES THEREFROM, THE TOTAL AMOUNT OF THE COMPOSITIONS OF (1) AND (2) WITH WHICH THE CELLULOSIC MATERIAL INITIALLY IS IMPREGNATED BEING SUCH THAT THE FINISHED FLAME-RESISTANT TEXTILE CONTAINS FROM ABOUT 10% TO ABOUT 75% BY WEIGHT, BASED ON THE DRY WEIGHT OF THE UNTREATED TEXTILE, OF WASHFAST IMPREGNANT. 